Improvement in boiler-tube scrapers



.|. B. CHRISTFFEL.

Boiler Tube Scrapers. y N0. 137,826.` PatentedApril15,l873.

UNITED STATES PATENT OEEroE.

JOHN B. OHRISTOFFEL, OF WILLIAMSBURG, NEW YORK.

IMPROVEMENT IVN BOlLERrTUBE SCRAPERS.

Specification forming part of Letters Patent No. 137,826, dated April15, 1873; application filed l February 15, 1873.

To all whom it may concern:

Beit known that I, JOHN B. CHRISTOFFEL, of Williamsburg, in the countyof Kings and State of New York, have invented a new and usefulImprovement in Boiler-Tube Scraper, of which the following is aspecilication:

Figure 1` is a side view of my improved scraper, part being broken awa-yto show the construction. Fig. 2 is a detail View of the collar and pinsfor holding the ends of the steel blades. A

Similar letters of reference indicate correspondin g parts.

My invention `has for its object to improve the construction of myboiler-tube scraper for which Letters Patent N o. 62,816 were granted tome March 12, 1867, so as to make it more convenient in use, moreeffective in operation, and less expensive in manufacture. The inventionconsists in the loose collars provided with radial pins, in combinationwith the rod, the spiral blades, and the coiled springs, and in thecombination of stops with thc rod and inner sides of the loose collars,as hereinafter fully described.

A is a rod, upon which are placed two movable collars, B, at` suitabledistances apart. Upon the collars B are formed or to them a-re attachedas many radial pins as there are designed to be blades O in the scraper.The

blades C are made of light spring-steehare arranged spirally, and haveholes in their ends to receive the pins of the collars B. The side edgesof the blades O may be notched to prevent them from coming in contactwith the adjacent pins. The ends of the blades O may be further securedin place upon the pins of the collars B by small wires passed aroundsaid ends, as shown in Fig. l. To the rod A, at the inner sides of thecollars B, are secured stops D, to prevent said collars from movingtoward each other while allowing them to move outward freely. The stopsD may be wires passed through the rod A, as shown in Fig. 1, or they maybe collars attached to or shoulders formed upon said rod. Upon the rodA, at the outer sides of thecollars B, are placed washers E,againstwhich rest the inner ends of the springs F, which are coiledaround said rod, as shown in Fig. 1. The outer ends of the coiledsprings E are supported by being passed through the said rod A, or bynuts screwed upon it.

This construction enables the scraper to adjust itself to the size ofthe tube to be oper ated upon, andadapts it to be used either endforward, as may be desired.

Having thus described my invention, I claim as new and desire to secureby Letters Patent-- 1. The springs G, notched and combined with theradial pins and movable collars, as described, to hold said springsfirmly to rod A, but allow them to readily contract and eXL pandthereon. r

2. The combination, with springs O secured as set forth, of the innerstops D D, the out side washers E, and the springs F, arranged andapplied as set forth.

' JOHN B. OHBISTOFFEL.

Witnesses:

J AMEs T. GRAHAM, T. B. MosnER.

